Phylogenetic analyses of the nitrogen-fixing genus Derxia

The Journal of General and Applied Microbiology

Cheng-Hui Xie¹  Akira Yokota¹ 

[1] Institute of Molecular and Cellular Biosciences, The University of Tokyo

关键词: cellular fatty acid;    Derxia;    nifH;    phylogeny;    β-Proteobacteria;    16S rDNA;   

DOI  :  10.2323/jgam.50.129

学科分类：微生物学和免疫学

来源: Applied Microbiology, Molecular and Cellulrar Biosciences Research Foundation

【 摘 要 】

Phylogenetic analyses of the 16S rRNA gene sequence indicate that the genus Derxia forms a distinct lineage in the β-Proteobacteria. On the NJ tree Derxia has a low bootstrap value (30.9%) with Alcaligeneceae, and on the ML tree it shows an independent cluster separated from other families. Moreover, there is below 93.4% 16S rDNA sequence similarity between genus Derxia and the genera of the β-Proteobacteria. These facts reveal that Derxia is not grouped with any known family of β-Proteobacteria and should be placed as a separate genus of β-Proteobacteria. The data on high G+C content (71 mol%), the cellular fatty acid composition, and the physiological characteristics of facultative hydrogen autotrophy and nitrogen fixation are unique for Derxia. The nifH gene sequence was found in this genus and phylogenetically compared among nitrogen-fixing bacteria to indicate that Derxia is clustered with the diazotrophs of β-Proteobacteria.

【 授权许可】

Unknown